Spinal Nerve RootsSpinal NervesSpinal CordPeripheral Nervous System NeoplasmsNerve Compression SyndromesLumbosacral RegionRadiculopathyLumbar VertebraeNeuralgiaSpinal Cord InjuriesSciatic NerveInjections, SpinalGanglia, SpinalPeripheral NervesMotor NeuronsMagnetic Resonance ImagingCauda EquinaNerve FibersSciaticaPeripheral Nerve InjuriesLigationLumbosacral PlexusHyperalgesiaNeurons, AfferentTooth RootPeripheral Nervous System DiseasesNerve RegenerationAxonsIntervertebral Disc DisplacementRats, Sprague-DawleyNerve BlockRhizotomyReflex, MonosynapticElectric StimulationReplantationCatsSpinal CanalSpinal Cord NeoplasmsNeural ConductionSpinal StenosisCervical VertebraePainLampreysReflexSacrumPain MeasurementMyelographyNerve Fibers, MyelinatedHindlimbPain ThresholdEpidural SpaceAutonomic Fibers, PreganglionicSpinal DiseasesOptic NerveLaminectomySpinal Cord DiseasesCervical PlexusSpinal Cord CompressionAction PotentialsStrychnine